Focus on Species
The focus here is on species. Subspecies and varieties may be mentioned in the notes, but are otherwise ignored. Cultivars are ignored. Sterile hybrids are ignored.
Focus on Hardy
Hardy, initially at least, is defined as those ferns which can withstand a winter minimum of -15ºC or about USDA Zone 7. Some relaxation is expected.
Focus on Cultivation
There are far more hardy fern species in the world than there are in gardens. Yes, most of the temperate ferns of North America and Europe are in cultivation, but most of the ferns of the Southern Hemisphere and of the Himalayas are not. Many eastern Asian ferns are only in cultivation there, and not accounted for here. The resources used in selecting species for inclusion here are listed in the bibliography.
What's Not Here
The site is about identifying hardy ferns. There is no shopping cart, no ads, no chat room. There is no How to Grow section.